JPH07176880A - Heat dissipating body and positive temperature coefficient thermistor device using the heat dissipation body - Google Patents

Abstract

PURPOSE:To obtain a heat dissipating body which is excellent in thermal conduc tion and heat dissipating efficiency and can obtain the optimum thermal effi ciency, by fixing the end surface parts of at least two radiation fins on one vacant surface of a base plate composed of metal material excellent in thermal conductivity, while forming a gap between the fins without stacking the surfaces. CONSTITUTION:A heat dissipating body 11 consists of a base plate 12 and a plurality of radiation fins 13, and the base plate 12 is composed of metal material excellent in thermal conductivity. The bottom part 13a of the fin 13 is made to abut against one main surface 12a of the base plate 12 and fixed, e.g. via heat-resistant adhesive agent 14. Hence the bottom part 13a is fixed on the base plate 12, and the heat dissipating body 11 is constituted by fixing two or more fins 13 on one main surface 12a of the base plate 12 in the manner in which the main surfaces of the fines are arranged almost parallel with each other and not stacked.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention mainly relates to a radiator used for a heater for generating warm air in heating equipment, drying equipment and the like, and a positive temperature coefficient thermistor device using the radiator.

[0002]

2. Description of the Related Art FIG. 4 and FIG.
It will be described based on. The heat radiator 1 is composed of a base plate 2 and heat radiation fins 3.

The base plate 2 is, for example, a substantially rectangular plate made of aluminum and having good heat conduction, and a plurality of caulking claws 4 at equal intervals along the long end face on one main surface 2a.
Are formed. The fin 3 is formed by, for example, repeatedly forming a strip thin plate made of aluminum with good heat conduction into a zigzag shape so as to have a substantially rectangular cross section, thereby forming a valley 3a and a peak 3b.

Then, the valley portion 3a of the fin 3 is brought into contact with one main surface 2a of the base plate 2, and the plurality of claws 4 on both end surfaces of the base plate 2 are caulked, whereby the base plate 2 is provided with the valley portion 3a side. The ends are fixed to form the radiator 1.

Two heat radiators 1 having such a structure are used, and the other main surfaces 2b of the base plates 2 are made to face each other,
Meanwhile, the well-known positive temperature coefficient thermistor element 5 (hereinafter referred to as PTC
The positive temperature coefficient thermistor device 6 is configured by electrically and thermally bonding (hereinafter abbreviated as “element”). When a voltage is applied between the two base plates 2 of the positive temperature coefficient thermistor device 6, the PTC element 5 generates heat, and the heat is conducted to the fins 3 via the base plates 2 and the fins 3
By radiating heat from the PTC thermistor device 6, the PTC thermistor device 6 functions as a heating element.

[0006]

However, in the radiator and the PTC thermistor device having such a configuration,
Since the fins are caulked and fixed to the base plate,
Microscopically, there is a partial space between the base plate and the fins, and the heat conduction between the base plate and the fins is low. Therefore, the heat conduction to the fins of the radiator is low, and the output efficiency of the PTC thermistor device is low. Further, since the fins are bent in a zigzag shape, there are problems in terms of processing and cost in freely setting the thickness of the fins and the pitch as the bending interval.

The object of the present invention is to solve the above-mentioned problems, good heat conduction and heat dissipation efficiency, and
An object of the present invention is to provide a radiator and a positive temperature coefficient thermistor device that can obtain optimum thermal efficiency according to the heat generation characteristics of the PTC element.

[0008]

Therefore, in the heat radiator of the present invention, at least two heat radiation fins are provided on one main surface of the base plate made of a metal material having good heat conduction with a gap therebetween. It is characterized in that its end face portion is fixed without overlapping its main surface.

The positive temperature coefficient thermistor device of the present invention is
The heat radiator is fixed to both main surfaces of the positive temperature coefficient thermistor element.

[0010]

That is, according to the present invention, the base plate and the fins are fixed to each other without caulking as described above, so that the heat conduction between the base plate and the fins is good and the fins are thickened. This increases the output efficiency of the PTC thermistor device.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of a radiator according to the present invention will be described below with reference to FIG. The heat radiator 11 is composed of a base plate 12 and a plurality of heat radiation fins 13. The base plate 12 is made of, for example, aluminum or a substantially square plate-shaped metal material having good heat conduction.

The fin 13 is made of, for example, aluminum or a metal material having good heat conductivity, has a bottom portion 13a formed by bending one end surface portion of a substantially rectangular plate at a substantially right angle, and has a substantially L-shaped cross section. It is what we are doing. And
The fins 1 are provided on one main surface 12a of the base plate 12.
3 abutting the bottom portion 13a, for example, the heat-resistant adhesive 14
The bottom portion 13 a is fixed to the base plate 12 by fixing the bottom portion 13 a to the base plate 12.

In this way, the radiator 11 has one main surface 12 of the base plate 12 so that the main surfaces of the fins 13 of two or more sheets are substantially parallel to each other and do not overlap each other.
It is configured by being fixed on a.

An embodiment of the positive temperature coefficient thermistor device (not shown) according to the present invention uses two of the above-mentioned radiators 11 and the other main surface 12b of the base plate 12 in the same manner as the conventional example shown in FIG. Face-to-face with PTC in between
It is configured by electrically and thermally bonding the element 5. When a voltage is applied between the two base plates 12 of this positive temperature coefficient thermistor device, the PTC element 5 generates heat, and the heat is transmitted through the base plate 12 to the fins 13.
By conducting heat to the fins and radiating heat from the fins 13,
The positive temperature coefficient thermistor device functions as a heating element.

The method for fixing the fins 13 to the base plate 12 is not limited to the heat-resistant adhesive, and the same means may be used for fixing. Also, without using an adhesive, for example, using a connecting means such as welding,
The bottom portion 13a of the fin 13 may be fixed to the base plate 12.

Next, a second embodiment of the radiator will be described with reference to FIG. The heat radiator 31 is composed of a base plate 32 and a plurality of heat radiation fins 33.

The base plate 32 is made of, for example, aluminum or a substantially square plate-shaped metal material having good heat conduction. Then, one main surface 32 of the base plate 32
A brazing material 34 made of aluminum having a melting point (T2 ° C.) lower than the melting point (T1 ° C.) of the metal material used for the base plate 32 is foil-shaped and connected onto the surface a.

On the other hand, the fin 33 is made of, for example, aluminum having a melting point similar to that used for the base plate 32 or a metal material having good thermal conductivity, and one end face portion of a substantially rectangular plate is bent at a right angle. It has a substantially L-shaped cross section having a bottom portion 33a formed by the above. A brazing material 35 made of aluminum having a melting point (T2 ° C.) lower than that of the metal material of the fin 33 is connected to the outer surface of the bottom 33a of the fin 33 in a foil shape.

Then, the outer surface of the bottom portion 33a of the fin 33 is brought into contact with one main surface 32a of the base plate 32, and brazing is performed, for example, using a vacuum furnace at T2.degree.
By holding the temperature below T1 ° C. for a certain period of time, the brazing materials 34 and 35 are melted to fix the bottom portion 33a of the fin 33 to the base plate 32.

In this manner, the radiator 31 has one main surface 32 of the base plate 32 in which the main surfaces of two or more fins 33 are substantially parallel to each other and do not overlap each other.
It is configured by being fixed on a.

The brazing material 34 on the base plate 32 and the brazing material 35 on the fins 33 may be connected to either one.

Next, a third embodiment of the heat radiator will be described with reference to FIG. The radiator 41 is configured by fixing the fins 33 on one main surface 42a of the base plate 42, and the PTC element (not shown) is conductively and thermally fixed to the other main surface 42b of the base plate 42. It is something. As the method of fixing the fins 33 on the main surface 42a of the base plate 42, the same connection method as in the first and second embodiments is used.

The base plate 42 is formed by bending both ends of the base plate 42 so that the PTC element 5 can be easily held, for example, as shown in FIG.

The shapes of the fins 13 and 33 are not limited to the substantially L shape, and the bottoms 13a and 33a are formed on the end faces.
It may have a flat plate shape without forming. In this case, the fixing to the base plates 12, 32, 42 is the side end face which is the end face portion of the fin. Also, the base plate 1
The angle formed by 2, 32, 42 and the main surface of the fin is not limited to a right angle, and may be any number as long as the main surfaces of the plurality of fins are substantially parallel.

[0025]

As described above, in the radiator according to the present invention and the PTC thermistor device using the radiator,
It has the following effects.

1. Since the base plate and the fins are firmly fixed to each other, there is no air layer between them and the heat conduction is good. Particularly, in the brazing process, good heat conduction could be obtained because the base plate and the fins are integrated in terms of heat conduction.

2. The thickness, height and spacing of the heat radiation fins can be freely selected, and fins having an optimum shape (for example, the fin thickness is thick) can be formed with respect to the size of the heat radiation body. . Then, it was possible to create a radiator with optimum thermal efficiency in accordance with the heat generation characteristics of the positive temperature coefficient thermistor device.

3. When fixing the fins to the base plate, there is no need for caulking, so it is not necessary to form caulking claws on the base plate, and the base plate is not required to have sufficient strength to withstand caulking. Therefore, the shape of the base plate can be freely formed except for one main surface, and it can also serve as a case of the PTC element like the base plate of FIG. 3, for example.

[Brief description of drawings]

FIG. 1 is a partially omitted perspective view of a first embodiment of a radiator according to the present invention.

FIG. 2 is a partially omitted perspective view of a second embodiment of a radiator according to the present invention.

FIG. 3 is a partially omitted perspective view of a third embodiment of a radiator according to the present invention.

FIG. 4 is a partially omitted perspective view of a conventional radiator.

FIG. 5 is a partially omitted side view of a conventional positive temperature coefficient thermistor device.

[Explanation of symbols]

 5 Positive Characteristic Thermistor Element 11, 31, 41 Heat Dissipator 12, 32, 42 Base Plate 12a, 32a, 42a One Main Surface 12b, 42b Other Main Surface 13, 33 Fin 13a, 33a End Face (Bottom)

Claims (3)

[Claims] 1. A base plate made of a metal material having good heat conduction, on one main surface of which at least two heat dissipating fins are spaced apart from each other and whose end faces are fixed to each other without overlapping the main surfaces. The heat radiator characterized by having done. 2. The fins are fixed to the base plate by using a brazing process.
The heat sink described. 3. A PTC thermistor device in which the other main surface of the base plate of the radiator according to claim 1 is bonded to both main surfaces of the PTC thermistor element.